yolov3 [1]} is an improved version of yolov2. The most salient feature of YOLOv3 is that it makes detections at three different scales, which are precisely given by downsampling the dimensions of the input image by 32, 16, and 8, respectively. Detections at different scales help address the issue of detecting small objects, a frequent complaint with YOLOv2. More, YOLOv3 proposes a deeper and robust backbone for features extraction, called Darknet-53 (in contrast with the Darknet-19 characterizing YOLOv2).
